Debian is an operating system for your computer that consists only of Free Software. It uses the Linux kernel, and a large part of the basic tools that fill out the operating system come from GNU, which are also free. It comes with thousands of packages.

Gentoo Linux is a versatile and fast Linux
distribution for x86, PowerPC, Sparc, and Sparc64
that's geared towards Linux power users. Unlike
other distros, it has an advanced package
management system called Portage. Portage is a
true ports system in the tradition of BSD ports,
but is Python-based and sports a number of
advanced features including dependencies,
fine-grained package management, "fake"
(OpenBSD-style) installs, path sandboxing, safe
unmerging, system profiles, virtual packages,
config file management, and more.

Mandriva is an RPM-based Linux distribtion. It excels at usability and simplicity, features thoroughly preconfigured KDE and GNOME desktops, and includes cool tools like supermount (transparent access to removable media) and DiskDrake (a full-featured graphical hard-drive partitioner). Unlike former versions, Mandriva is not a tuned-up Red Hat, but a very mature Linux distribution on its own. Mandriva is published by a company, but is a completely open and transparent free-software project.

Red Hat Linux is a versatile distribution that can be a server or desktop at work or at home. Everything you need to set Red Hat Linux up as a Web server, email server, DNS server, news server, and more is included, along with software for email, browsers, publishing, calendars, Internet tools, and much more.

Slackware is the longest-running distribution of the Linux operating system. Slackware offers a stable and secure version of Linux that is perfect for home, office, or educational use. Slackware is easy for beginners to install, but contains all the advanced features required by the experienced UNIX power-user.

SmoothWall Express is a network firewall, designed
with home and small business users in mind. It is
based upon a security-hardened subset of the
GNU/Linux operating system and is completely free
to use, download, and distribute. SmoothWall
Express offers facilities and features normally
only seen in expensive commercial offerings.

tomsrtbt is the most Linux on one floppy disk for rescue recovery panic and emergencies, contains tools to keep in your shirt pockets, is useful whenever you can't use a hard drive and contains about 100 rescue tools.

Devil-Linux is a special secure Linux distribution which is used for firewalls, routers, gateways, and servers. The goal of Devil-Linux is to have a small, customizable, and secure Linux system. Configuration is saved on a floppy disk or USB stick, and it has several optional packages. Devil-Linux boots from CD, but can be stored on CF cards or USB sticks.

ALT Linux is a set of Linux distributions that are
based on Sisyphus, an APT-enabled RPM package
repository that aims to achieve feature
completeness, usability, and security in a
sensible and manageable mixture.